Photographic viscous processing

ABSTRACT

The processing of color photographic films is accelerated and viscous pastes are used for bleaching and fixing by color developing color-photographic images first coating a viscous fixing paste on the developed material and coating on thereafter a viscous bleaching paste. Thereafter the layers of the fixing and bleaching pastes are sprayed off with water and finally the color photographic material is rinsed in water.

United States Patent Inventors Appl. No.

Priority Karl-Wilhelm Schranz Opladen;

Erwin Schon, Leverkusen, both of Germany Oct. 1, 1968 Sept. 21, 1971 Afga-Gevaert Aktiengesellschaft Leverkusen, Germany Oct. 14, 1967 Germany PHOTOGRAPHIC VISCOUS PROCESSING 4 Claims, N0 Drawings US. Cl 96/55, 96/62, 96/60, 96/61 Int. Cl G03c 5/38 Field of Search 96/50, 60, 61, 62, 55

i 56] References Cited UNITED STATES PATENTS 3,189,452 6/1965 Pard 96/56 X 3,293,036 12/1966 Meckl 96/60 FOREIGN PATENTS 739,202 10/1955 Great Britain 96/60 Primary Examiner-William D. Martin Assistant Examiner-william R. Trenor Attorney-Connolly and Hutz PHOTOGRAPHIC VISCOUS PROCESSING PHOTOGRAPHIC VISCOUS PROCESSING The invention relates to a method of processing exposed color photographic materials, the bleaching and fixing being effected with viscous pastes.

The conventional processing of color-photographic materials comprises, development, bleaching and fixing. It is necessary to rinse the material very thoroughly after color-forming development and before the treatment with the bleaching bath in order to remove substantially all the excess developer. This is necessary, because the surplus developer would itself be oxidized in the bleaching bath and react in the oxidized form with color-couplers to yield an undesirable color fog. Times of l520 minutes are necessary for this rinsing, so that this step takes up a large part of the processing time.

The liquid processing baths for bleaching can be replaced by viscous pastes, which contain the necessary processing agents. This paste is applied by conventional devices as a layer on the exposed photographic material. After this treatment, this layer is sprayed off with water. However, when using viscous pastes the long rinsing of the developed material could not be avoided. Up until now the use of such pastes has consequently been restricted to the processing of black-and-white materials and to the developing step when processing color photographic films.

It is among the objects of the invention to accelerate the processing of color-photographic films and to modify the processes so that viscous pastes can also be used for the bleaching and fixing.

We now have found that the time-consuming rinsing between the color development and further processing can be avoided if, in contrast to the conventional sequence a viscous paste which contains the fixing agent is first applied, and then another layer of a viscous paste which contains the bleaching agent is applied. It is highly unexpected no fogging to occur when processing in accordance with the invention, although rinsing only took place for a short time after the development. when using viscous developer pastes, the conventional spraying off of the processing layer with spray nozzles is sufficient.

It is usually desirable to apply the paste containing the bleaching agent immediately after the paste containing the fixing agent has been applied, but the advantages of the method according to the invention are also obtained if there is a brief time interval between the applications.

The processing method according to the invention, makes it possible to shorten successfully the wet processing time for color-photographic negative material by about 50 percent. Similarly the time needed for the wet processing of colorphotographic positive and reversal materials can also be considerably shortened.

The conventional arrangements can be used for the application of the processing layers. The layer thicknesses of the pastes containing the fixing agent and the bleaching agent are preferably between 0.1 and 1 mm., advantageously between 0.3 and 0.5 mm. The most suitable thickness of thelayer, depends on the concentration of the active substance in the layer, on the photographic material and on the required processing time. The most favorable conditions can be easily established by simple routine tests.

The viscosity of the processing pastes at 50 C. is between 300 and 2000 c.p.s., preferably between 1000 and 1300 c.p.s. It has been found desirable that the viscosity of the bleaching paste be somewhat less than that of the fixing paste. The processing can be carried out at temperatures between and 70 C., preferably between and 40 C.

The processing pastes have the usual compositions. They differ substantially from the conventional baths in that they contain thickeners which produce the pasty consistency. Processing baths which can be used are described in the book by H. Berger Agfacolor 1962, or in he work by E. MUtter Farbphotographie, Theorie und Praxis, Springer Verlag, Vienna 1967. Suitable thickeners for such baths are: cellulose,

derivatives of cellulose such as cellulose ethers, for instance hydroxyethyl cellulose or carboxymethyl cellulose; starch or derivatives thereof; alginates or derivatives thereof, such as salts, carrhagenates, synthetic thickeners such as polyvinyl pyrrolidone, polyvinyl alcohol or other water-soluble polymers, for example, the semiarnide of the copolymer of methyl vinyl ether and ammonium maleate.

EXAMPLE A convention commercial color-photographic material comprising a red-sensitive layer containing a cyan coupler arranged on a support, a green-sensitive layer containing a magenta coupler and a blue-sensitive layer containing a yellow coupler is exposed and developed with a developer having the following conposition:

sodium hcxametaphosphate 2 g. diethyl parapheylene diamine sulfate 2.75 g. hydroxylamine sulfate 1.2 g. anhydrous sodium sulfite 2 g. anhydrous potassium carbonate 75 g potassium bromide 2 g.

ammonium thiosult'ate g. anhydrous N21 50:, 15 g. H B0 7.5 g. glacial acetic acid l0 ml. hydroxyethyl cellulose l l g. octyl sulfosuccinamide 2 ml.

pH 4.9 viscosity l l 10 c.p.s.

the layer thickness is 0.6 mm.

Immediately afterwards a bleaching paste having the following composition is applied in a thickness of 0.3 mm. using a second extruder:

KBr 20 g. potassium ferricyanide I00 g. hydroxyethyl cellulose l l g. octyl sulfosuccinamide 4 ml.

pH 6.0-7.5 viscosity 1020 l0220 c.p.s.

After leaving the film for 4 minutes at 30 C., both layers are rinsed off using a flat jet nozzle and the film is then rinsed in water.

A colored image with satisfactory color reproduction is obtained. The sensitometric testing of the image which is obtained, when compared with an image which has been obtained using the same material, but which has been processed with conventional liquid baths, shows no differences.

if the processing with the viscous pastes is carried out in the usual manner, i.e. first treating the film with the bleaching bath and then with the fixing bath, a colored image is obtained which shows strong color foggingas is usual when no intermediate rinsing with water has been effected. Such images are of no practical value.

What is claimed is:

ing agent and that layer is overcoated with a second layer containing a ferricyanide bleaching agent.

2. The process of claim 1, wherein the thicknesses of the layer-containing fixing agent and the layer containing the bleaching agent are 0.1-1 mm.

3. The process of claim 1, wherein the viscosity of the processing pastes is between 300 and 2000 c.p.s. at 50C.

4. The process of claim 1, wherein the processing temperature is between 25 and 40 C gig-I UNITED S'iik'li'lb' IATI'INT OFFICE 9} 'w 11 \T" 1 r CERTH'ICALL O1 CORhnClION Pate X 3', 0?,277 W Inwntofls) KARL-WIIHEIM SCHRANZ and ERWIN SCI-ION It is certified that error appears in the above-identified patent and that: said Letters Patent are hereby corrected as shown below:

Eolumn 2, line 26, "later" should read liter Column 2, line 39, delete the straight line following "H B0 Column 2, line "c.p.s. should follow "1110".

001mm 2, line 5 delete 'l022O" so line will read viscosity 1020 c.p.s.

Claim 1, line 5, delete "fixing".

Signed and sealed this 2nd day of May 1972.

(SEAL) Attest:

EDWARD M.FLETGHER, JR. ROBERT GO'I'ISCHALK Attesting Officer Commissioner of Patents 

2. The process of claim 1, wherein the thicknesses of the layer-containing fixing agent and the layer containing the bleaching agent are 0.1- 1 mm.
 3. The process of claim 1, wherein the viscosity of the processing pastes is between 300 and 2000 c.p.s. at 50* C.
 4. The process of claim 1, wherein the processing temperature is between 25* and 40* C. 